Donned and doffed headset state detection

ABSTRACT

An apparatus and method are provided for determining the donned or doffed state of a headset. In one example, a headset includes a processor, an acoustic transducer, and a detector operably coupled to the processor, the detector providing an output charge pattern corresponding to a state selected from the group consisting of the headset being donned and doffed. Advantageously, the present disclosure provides for reliably determining a donned or doffed state of a headset for efficiently routing calls, text messages, and/or otherwise being used for notifications and requests in a system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Utility application Ser. No.11/542,385, filed Oct. 2, 2006, which is incorporated herein in itsentirety for all purposes.

TECHNICAL FIELD

The present invention relates generally to headset devices and, moreparticularly, to a method for determining when a headset is donned anddoffed and a headset therefor.

BACKGROUND

Telephone headsets are used in various environments, such as callcenters and offices, and a method and apparatus for determining whethera person is available at his or her telephone, computer, or work stationallows for more efficient automation of many business processes.

For example, if an automated call distribution system at a call centerreceives a large number of incoming calls, a means and method todetermine which of its local stations are connected to headsetspresently worn by an agent allows for efficiency in routing calls.

In another example, in circumstances common in many businesses, anindividual may use multiple different telephones or headsets over thecourse of a day. Such telephones may include cellular telephones,conventional analog or digital telephones, Internet Protocol (IP)telephones, and computers running software which acts as an IPtelephone. If the headsets worn by the individual in the course of usingthese different telephones can determine when they are actually beingworn, this state can be communicated to call routing devices so thatcalls for that individual can be efficiently routed to the telephone heor she is currently using.

Previously, the detection of current flow to a headset has been used todetermine that a headset is physically connected to a particulartelephone, and then the inference is made that because a headset isphysically connected, a person must be available at that telephone orheadset. This inference fails, however, when the user removes theheadset from his head and leaves the headset behind still connected tothe telephone, computer, and/or system. For example, a home user mayhave no need to remove the headset from the computer when the userdeparts from the system.

Another previous means and method for determining a headset state hasincluded software that requires the user to login to indicate that theuser is available to receive calls. Again, if the user moves away fromthe computer without logging out, the system will erroneously indicatethe user's availability at that computer.

In another application, the ADA has established a requirement fortelephone earphone volume control that provide increased volume forusers with significant hearing loss. This requirement mandates that atelephone with extended receive volume control range must reduce thevolume to a safe level appropriate for a user that does not suffer fromsignificant hearing loss whenever the user has hung up the telephone.This requirement is intended to protect the hearing of a telephone userthat does not suffer from significant hearing loss when the user uses atelephone that is normally used by a person that does suffer fromsignificant hearing loss.

Previous solutions have reduced the receive volume after each call, butthis solution has caused great inconvenience to the user withsignificant hearing loss in that the user must manually return thereceive volume to the previous level at the start of each phone call.This is particularly onerous in call center and office environmentswhere the user handles many calls per hour.

In many consumer systems, plugging in and unplugging a headset as wellas logging in and out of a system may be inconvenient, easily forgotten,and/or too unreliable. Thus, a reliable means and method for determiningthe donned or doffed state of a headset is highly desirable forproviding notification to a system.

SUMMARY

The present invention provides an advantageous apparatus and method fordetermining the donned or doffed state of a headset.

In one embodiment of the present invention, a headset is provided, theheadset comprising a processor, an acoustic transducer, and a detectoroperably coupled to the processor, the detector providing an outputcharge pattern corresponding to a state selected from the groupconsisting of the headset being donned and doffed.

In accordance with another embodiment of the present invention, anotherheadset is provided, the headset comprising a processor, an acoustictransducer, and a detector operably coupled to the processor, whereinthe detector provides an output charge pattern, and further wherein thedetector is selected from the group consisting of a motion detector anda non-motion detector. The headset also includes a circuit operablycoupled to the detector for determining whether the output chargepattern corresponds to a state selected from the group consisting of theheadset being donned and doffed.

In accordance with yet another embodiment of the present invention, amethod of determining a headset state is provided, the method comprisingproviding a headset including a processor, a detector operably coupledto the processor, and a donned-doffed recognition circuit operablycoupled to the detector, and detecting a headset characteristic selectedfrom the group consisting of kinetic energy, temperature, andcapacitance. The method further includes transforming the detectedheadset characteristic into an output charge, and processing a pluralityof output charges to determine an output charge pattern corresponding toa state selected from the group consisting of the headset being donnedand doffed.

Advantageously, the present invention allows for the efficient routingof calls and messages to donned headsets and for maintaining volumesettings between calls for hearing impaired users while protecting thehearing of a non-hearing impaired user who subsequently uses the sametelephone or headset.

The scope of the invention is defined by the claims, which areincorporated into this section by reference. A more completeunderstanding of embodiments of the present invention will be affordedto those skilled in the art, as well as a realization of additionaladvantages thereof, by a consideration of the following detaileddescription of one or more embodiments. Reference will be made to theappended sheets of drawings that will first be described briefly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a system including a headset server and a headset (wired orwireless) capable of indicating a donned or doffed state of the headsetin accordance with an embodiment of the present invention.

FIG. 2 shows a block diagram of a headset capable of indicating a donnedor doffed state in accordance with an embodiment of the presentinvention.

FIGS. 3 through 6 show different embodiments of a motion detector usedin a headset in accordance with the present invention.

FIGS. 7 through 13 show different embodiments of a non-motion detectorused in a headset in accordance with the present invention.

FIG. 14 is a flowchart showing a method of determining a donned ordoffed state of a headset in accordance with embodiments of the presentinvention.

Embodiments of the present invention and their advantages are bestunderstood by referring to the detailed description that follows. Itshould be appreciated that like reference numerals are used to identifylike elements illustrated in one or more of the figures.

DETAILED DESCRIPTION

The present invention provides an advantageous apparatus and method fordetermining the donned or doffed state of a headset.

Referring now to FIG. 1, a system 100 is illustrated in accordance withan embodiment of the present invention. System 100 includes a headset102 and a headset server 104 operably coupled together. Other elementsmay be between headset 102 and server 104, such as but not limited to,adaptors, access points, and/or networks. It is noted that server 104may be used to route calls to multiple headsets, for example, at a callcenter.

Headset 102 may be wired or wireless. In one example, headset 102 may bewired to an adaptor which is coupled to a network, or headset 102 may bewirelessly coupled to an access point (AP) (not shown), which isoperably coupled with a network. In one example, the network may be acommunications network which may include a public switched telephonenetwork (PSTN), an integrated services digital network (ISDN), a localarea network (LAN), and/or a wireless local area network (WLAN), thatsupport standards such as Ethernet, wireless fidelity (WiFi), and/orvoice over internet protocol (VoIP).

In one example, an AP includes a transceiver and a processor configuredto allow a wireless device (e.g., a headset) access to a networkconnected to the access point (e.g., via a 10/100 Ethernet RJ-45 port).An AP may be any device that allows wireless-equipped computers andother devices to communicate with a wired network. In one example, an APis able to support WiFi in general, and the 802.11a, 802.11b, and/or802.11g wireless networking standards in particular. In other examples,the AP may be able to support other wireless networking standards.

Referring now to FIG. 2 in conjunction with FIG. 1, a block diagram ofan example of headset 102 is shown in accordance with an embodiment ofthe present invention. Headset 102 includes a processor 202 operablycoupled via a bus 214 to a detector 204, a donned and doffeddetermination circuit 205, a memory 206, a transducer 208, an optionalnetwork interface 210, and an optional user interface 212.

Processor 202 allows for processing data, in particular managing databetween detector 204, determination circuit 205, and memory 206 fordetermining the donned or doffed state of headset 102. In oneembodiment, processor 202 may also process information about accesspoints, service providers, and service accounts for wireless headsets.In one example, processor 202 is a high performance, highly integrated,and highly flexible system-on-chip (SOC), including signal processingfunctionality such as echo cancellation/reduction and gain control inanother example. Processor 202 may include a variety of processors(e.g., digital signal processors), with conventional CPUs beingapplicable.

Detector 204 includes a motion detector and/or a non-motion detectorproviding output charges based upon a headset characteristic such askinetic energy, temperature, and/or capacitance.

In the case of a motion detector, as the user wears the headset, subtlemovements of the head (e.g., from standing, sitting, walking, orrunning) cause movements of the headset, and detector 204 transferskinetic energy from head and body movement into an electromotive force,or an output charge. In other words, motion of the headset induces asmall fluctuating current flow in a nearby electrical conductor. Currentin this conductor is amplified electronically. The output charges may beprovided at predetermined or varying intervals (e.g., sampling every 5seconds) and for predetermined or varying periods (e.g., based on timeor number of samples) to form an output charge pattern.

Detector 204 is operably coupled to a determination circuit 205 fordetermining whether a plurality of the output charges form an outputcharge pattern corresponding to a state selected from the groupconsisting of the headset being donned and doffed. In one example,determination circuit 205 compares the output charge pattern to apredetermined profile, and if the pattern is within the bounds of thepredetermined profile, the headset is considered to be in a state ofbeing donned. When there is no recognized output charge pattern for apredetermined period, then the headset may be considered to be abandonedand in a state of being doffed. In another embodiment, the output chargepattern may be recognized as a doffed output charge pattern. The outputcharges may be shaped using a comparator circuit which is connected toan input pin on a general purpose microcontroller. Firmware in themicrocontroller may implement a filtering algorithm to discriminatebetween movement of a headset when doffed and the occasional movementscaused by relocating a non-worn headset from one location to another. Inthis example, determination circuit 205 is an individual componentoperably coupled to other components of headset 102 via bus 214, butdetermination circuit 205 may be placed in various places as shown bythe dashed line connection, for example being integrated with processor202 or detector 204, stored in memory 206, or being provided fromoutside of headset 102, for example at server 104.

In the case of a non-motion detector, as the user wears the headset,detector 204 transfers temperature and/or capacitance readings into anelectromotive force, or an output charge. Current in this conductor isamplified electronically and processed as described above with respectto motion detectors. Again, the output charges may be provided atpredetermined or varying intervals and for predetermined or varyingperiods to form an output charge pattern.

Memory 206 may include a variety of memories, and in one exampleincludes SDRM, ROM, flash memory, or a combination thereof. Memory 206may further include separate memory structures or a single integratedmemory structure. In one example, memory 206 may be used to storepasswords, network and telecommunications programs, and/or an operatingsystem (OS). In one embodiment, memory 206 may store determinationcircuit 205, output charges and patterns thereof from detector 204, andpredetermined output charge profiles for comparison to determine thedonned and doffed state of a headset.

Transducer 208 may include an acoustic transducer, such as a microphone,a speaker, or a combination thereof, for transmission of sound (such asfrom the user's mouth or to the user's ear based upon signals from anaudio source). Transducer 208 may also include a plurality of separatetransducers for performing different functions. The transducer can beany type of electromagnetic, piezoelectric, or electrostatic type ofdriving element, or a combination thereof, or another form of drivingelement, for generating sound waves from the output face of thetransducer. In one embodiment, the transducer may receive signalsthrough wireless communication channels, such as by Bluetooth™ protocolsand hardware, in one example.

Network interface 210 allows for communication with APs, and in oneexample includes a transceiver for communicating with a wireless localarea network (LAN) radio transceiver (e.g., wireless fidelity (WiFi),Bluetooth, ultra wideband (UWB) radio, etc.) for access to a network(e.g., a wireless LAN or the Internet), or an adaptor for providingwired communications to a network. In one example, network interface 210is adapted to derive a network address for the headset using theheadset's electronic serial number, which is used to identify theheadset on the network. In one embodiment, the electronic serial numbermay be the headset's Media Access Control (MAC) address; however, theelectronic serial number may be any number that is mappable to a networkaddress. Network interface 210 is adapted to communicate over thenetwork using the network address that it derives for the headset. Inone embodiment, network interface 210 is able to transmit and receivedigital and/or analog signals, and in one example communicates over thenetwork using IP, wherein the network interface uses the headset's MACaddress or another globally unique address as its IP address. Inparticular, network interface 210 may be operably coupled to a networkvia the IEEE 802.11 protocol. However, the network interface 210 maycommunicate using any of various protocols known in the art for wirelessor wired connectivity.

An example of an applicable network interface and the Internet protocollayers (and other protocols) of interest for the present invention aredescribed in pending U.S. patent application Ser. No. 10/091,905 filedMar. 4, 2002, the full disclosure of which is hereby incorporated byreference for all purposes.

User interface 212 allows for manual communication between the headsetuser and the headset, and in one example includes an audio and/or visualinterface such that a prompt may be provided to the user's ear and/or anLED may be lit.

Referring now to FIGS. 3 through 13, different embodiments of detector204 are described in accordance with the present invention. FIGS. 3through 6 illustrate examples of motion detectors, and FIGS. 7 through13 illustrate examples of non-motion detectors in accordance with thepresent invention.

FIGS. 3A and 3B illustrate a magnet 302 and a conductor 304, such as acoil, that move relative to one another such that an output charge isgenerated in accordance with an embodiment of the present invention.FIG. 3A illustrates a movable magnet 302 that moves relative to a fixedconductor 304, and FIG. 3B illustrates a movable conductor 304 thatmoves relative to a fixed magnet 302. The movable component may behinged, suspended mechanically, or otherwise movably coupled so thatgravity or inertia drives slight movement with respect to the headsetwhenever the headset wearer moves his head or body. In one example, thefixed magnet may be the same magnet used in a moving-coil transducercontained in the headset. The induced current in the conductive elementis amplified, sent to a donned and doffed determination circuit (forexample a part of a printed circuit board assembly), and processed asdescribed above to determine a state of the headset.

FIGS. 3C through 3E illustrate in more detail embodiments of magnet 302movable with respect to a fixed conductor 304 in accordance with thepresent invention. FIGS. 3C, 3D, and 3E show a movable magnet 302 and afixed conductor 304, which is operably coupled to a printed circuitboard assembly (PCBA) 306.

In FIGS. 3C and 3D, magnet 302 is movably coupled to magnet support 308via a joint 310, which allows magnet 302 to move in various directionsrelative to conductor 304. In FIG. 3C, joint 310 may include aball-and-socket type joint slidably coupled along support 308 allowingmagnet 302 to move over trace conductor 304. In FIG. 3D, joint 310 mayinclude a spring that allows magnet 302 to move along an interior ofcoil conductor 304. In FIG. 3E, magnet 302 is movable within support308, which is filled with a fluid 310, in one example a ferrofluid,allowing magnet 302 to move along an interior of coil conductor 304 thatsurrounds at least a portion of support 308.

FIG. 3F shows a similar detector as in FIG. 3E, including magnet 302,PCBA 306, support 308, and fluid 310, but instead of conductor 304, asensor 312 is positioned proximate to support 308 for sensing movementof magnet 302 (e.g., sensing if the magnet passes the sensor). In oneexample, with no intent to limit the invention thereby, sensor 312 mayinclude a Hall effect sensor, a reed switch, and/or an optical switch.

FIG. 4A illustrates an acceleration sensor 402 operably coupled to aPCBA 406 in accordance with an embodiment of the present invention. Inone example, acceleration sensor 402 includes a mass affixed to apiezoelectric crystal. The mass is coupled to a supporting base throughthe piezoelectric crystal. When the sensor is subjected to kineticactivity, the sensor experiences force due to the acceleration of themass, thereby exerting a force on the crystal. This force results in anoutput charge of the crystal that is directly proportional to the inputacceleration. The variations in force against the crystal resulting fromthe movements of the headset result in various output charges. Theoutput charge is amplified, sent to a donned and doffed determinationcircuit, and processed as described above to determine a state of theheadset.

Examples of applicable micro-electronic mechanical acceleration sensors,such as piezoelectric accelerometers, are dual and tri-axisaccelerometers model series KXM and KXP, available from Kionix, Inc. ofIthaca, N.Y. Various piezoelectric crystal materials may be used for theaccelerometer construction, such as ceramic lead metaniobate, leadzirconate, lead titanate, and natural quartz crystal. Various mechanicalconfigurations of the masses and crystals may also be used, includingbut not limited to isolated compression, shear, and ring shear, to namea few.

In another embodiment, acceleration sensor 402 may include strain gaugesin one or more axes of the headset, as illustrated in FIGS. 4B, 4B1, and4B2. In one example, detector 204 includes a mass 420 coupled to an endof a flexible membrane 424 and thin electrical traces 422 (strain gaugeelement) on flexible membrane 424 and operably coupled to PCBA 406.FIGS. 4B1 and 4B2 illustrate membrane 424 flexing along oppositedirections, respectively, as illustrated by the arrows. The flexing ofmembrane 424 effectively lengthens and thins (flexes, compresses, and/orelongates) the traces 422, increasing the resistance through the tracepattern. Kinetic energy from movement of the headset causes variationsin the resistance of the trace pattern, thereby allowing fordetermination of a donned or doffed state of the headset.

FIGS. 5A and 5B illustrate a detector 204 including a movable conductor502 and a capsule 508 having electrical contacts 504 in accordance withan embodiment of the present invention. FIG. 5A illustrates conductor504 that is loosely contained within capsule 508, and FIG. 5Billustrates conductor 502 that is suspended within capsule 508.Conductor 502 is made of electrically conductive material and movablesuch that gravity and/or inertia causes conductor 502 to move withrespect to the headset whenever the headset wearer moves the headset.Electrical contacts 504 are positioned within capsule 508 such thatcontact with movable conductor 502 causes an electric current or outputcharge to be produced, which is amplified, sent to a donned and doffeddetermination circuit, and processed as described above to determine astate of the headset.

In FIG. 5A, conductor 502 closes a circuit by bridging a gap betweenelectrical contacts 504, allowing an electric current to flowintermittently. In FIG. 5B, conductor 502 is suspended from a pivotpoint inside the headset so that headset movement causes the conductorto move and touch contact points that surround the conductor,effectively closing and opening a circuit to thereby allow electriccurrent to flow intermittently.

In another example, the electrical contacts may be configured in groupsof two or more sets so that the motion of the weight in differingdirections may be registered, thereby providing more data fordetermining the headset state. For example, a movable conductive mass isloosely contained in a housing that includes many contacts, such thatmovement of the mass opens and closes circuits as the mass makes andbreaks contact with the housing contacts. The sensitivity of thisdetector can be tuned to detect the axis or direction of the movement,where alternate contacts are connected to different points on thecircuit. Accordingly, this configuration can be arranged to determinewhen the user of the headset is shaking his or her head fromside-to-side or nodding up and down, differentiating between the twomotions by monitoring which circuit(s) are opening and closing, therebyallowing the user to input information into the headset, such as whenresponding to a call-answer prompt with a nod “yes” or shake of the head“no”.

FIGS. 5C, 5C1, 5C2, and 5C3 illustrate in greater detail an embodimentof a detector 204 including a movable conductor 502 and a fixed capsule508 having electrical contacts 504 operably coupled to a PCBA 506.Conductor 502 is freely movable within spherical capsule 508 (as shownby arrows in FIG. 5C1), and creates or closes different circuits 512 asconductor 502 makes contact with electrical contacts 504 (as shown byFIGS. 5C2 and 5C3).

FIGS. 6A and 6B illustrate a detector 204 including a light source 602,a photosensor 606, and a movable reflective surface 604, 608therebetween in accordance with an embodiment of the present invention.FIG. 6A illustrates surface 604 that may be suspended, pinned, orloosely trapped, such that surface 604 at a rest state allowsphotosensor 606 to receive light from light source 602. Movement of theheadset causes surface 604 to move such that photosensor 606 detects achange in the amount of light received and induces fluctuating currentflow in a nearby electrical conductor. Alternatively, in FIG. 6B,surface 608 may be suspended, pinned, or loosely trapped, such thatsurface 608 at a rest state impedes light from reaching photosensor 606.Movement of the headset causes surface 608 to move such that photosensor608 detects a change in the amount of light received and inducesfluctuating current flow in a nearby electrical conductor. The currentflow or output charge produced is amplified, sent to a donned and doffeddetermination circuit, and processed as described above to determine astate of the headset. In yet another example, surface 604, 608 couldinclude a hole through which light from light source 602 travels,thereby providing changed amount of light received by photosensor 606 asthe surface 604, 608 moves as the headset is moved.

As noted above, detector 204 may include a non-motion detector thatprovides output charges based upon a headset characteristic such astemperature and/or capacitance. When a headset is properly worn, severalsurfaces of the headset touch or are in operable contact with the user.These touch/contact points can be monitored and used to determine thedonned or doffed state of the headset.

FIG. 7 illustrates an infra-red (IR) detector 702 that is sensitive tothe temperature of a human body. Humans having a skin temperature ofabout 93 degrees Fahrenheit, radiate infra-red energy with a wavelengthbetween about 9 and 10 micrometers. Therefore, the IR detector may beconfigured to be sensitive in the range of 8 to 12 micrometers, and maybe positioned to aim at a point where the headset is intended to contacta user's skin, such as the user's skin or hair. When the headset userdons the headset, the IR detector 702 detects radiation in thewavelengths between 9 and 10 micrometers and provides an electricalsignal or output charge that is amplified, sent to a donned and doffeddetermination circuit, and processed as described above to determine astate of the headset.

FIGS. 8A and 8B illustrate a pyroelectric sensor 802 that is positionedin close proximity to a point where the headset is intended to contact auser's skin. The sensor detects a user is present by determining a skintemperature near 93 degrees Fahrenheit and then providing an electricalsignal or output charge that is amplified, sent to a donned and doffeddetermination circuit, and processed as described above to determine astate of the headset. As shown in FIG. 8B, two pyroelectric sensors 802a and 802 b may be used, with one sensor positioned close to a contactpoint and the other positioned in a location away from a contact point.Differences (a delta) between the readings of the two sensors can beused to determine a donned or doffed state of the headset, for exampleif the delta of the two temperature readings is at or above apredetermined level.

FIG. 9 illustrates an electronic circuit 902 sensitive to capacitancepositioned in close proximity to a point where the headset is intendedto contact a user's skin. The circuit detects an increase in capacitancewhen the headset is worn and provides an output charge that isamplified, sent to a donned and doffed determination circuit, andprocessed as described above to determine a state of the headset.

Other detectors that may be used at a touch point includemicro-switches, as shown in FIG. 10. A micro-switch 1002 can be housedand operably coupled to a PCBA 1006 within the headset device such thatan actuator 1004 of the switch is positioned at a touch point 102 a ofthe headset, thereby being depressed when the headset is worn. Adetermination circuit in PCBA 1006 can monitor the state of the switch,thereby determining the state of the headset.

Another detector that may be used includes an inductive proximity sensor1102, as shown in FIG. 11. A proximity switch 1102 can be housed andoperably coupled to a PCBA 1106 within the headset device such that theswitch 1102 is positioned at a touch point 102 a of the headset, therebybeing triggered or activated when the headset is worn. This use of aproximity switch does not require force from the user's skin, butproximity to the user (without consistent force) such that a change inmagnetic field is detected is sufficient to trigger the sensor. Adetermination circuit in PCBA 1106 can monitor the state of the switch,discriminating between a donned or doffed state of the headset.

Yet another detector that may be used includes a skin resistivity sensor1202, as shown in FIG. 12. Conductive materials 1202 can be used at twoor more touch points 102 a on the headset, and a circuit in PCBA 1206can monitor the resistance between these conductive materials, therebydetecting a resistance that is consistent with a predetermined range,thus discriminating between a donned and a doffed state of the headset.That is, when the two or more contact points are in contact with theuser's skin, the resistance reading between these contact points will bedifferent from when the headset is not worn, for example the resistancebeing reduced when the headset is worn due to the skin addingconductance.

Referring now to FIG. 13, another detector that may be utilized includesa carbon dioxide (CO₂) sensor 1302 operably coupled to a PCBA 1306 and achannel 1304 in accordance with an embodiment of the present invention.Sensor 1302 is able to detect an increase of CO₂, thereby inferring adonned state of a headset. In one embodiment, sensor 1302 is able tosubtract background CO₂ levels to more accurately discriminate betweendonned and doffed states, and in another embodiment, sensor 1302 and adetermination circuit are able to detect patterns of CO₂ levelscorrelating to human breathing patterns.

It is noted that a variety of detectors that provide an output chargepattern corresponding to a donned or doffed state of a headset arewithin the scope of the present invention.

In critical applications, two or more of the embodiments described abovemay be used in one headset in order to determine a donned or doffedheadset state with greater accuracy and reliability. For example, in onecase with one motion detector and one non-motion detector being used, aheadset state can be indicated when both detectors indicate the samestate.

Referring now to FIG. 14 in conjunction with FIGS. 1 and 2, a flowchartof a method for determining the donned or doffed state of a headset isillustrated in accordance with an embodiment of the present invention.At step 1402, a headset characteristic, such as kinetic energy,temperature, and/or capacitance, is detected by a detector 204. At step1404, the detector provides an output charge corresponding to a detectedcharacteristic. The output charge is amplified and transferred todetermination circuit 205. At step 1406, a plurality of output chargesare processed by determination circuit 205 to determine an output chargepattern. At step 1408, determination circuit 205 correlates the outputcharge pattern to a donned or doffed state of a headset, in one examplecomparing the output charge pattern to predetermined output chargeprofiles that reflect a donned or doffed state of a headset. Thepredetermined output charge profiles may be in look-up tables or adatabase and may include a variety of parameters, such as for particularheadsets and detectors being used. At step 1410, the headset state maybe sent to server 104 for routing of calls or messages, or for notifyinga system regarding volume control for hearing impaired use.

Advantageously, the present invention provides a headset and method forreliably determining a donned or doffed state of a headset forefficiently routing calls, text messages, and/or otherwise being usedfor notifications and requests in a system. For example, the presentinvention allows for maintaining volume settings between calls forhearing impaired users while protecting the hearing of a non-hearingimpaired user who subsequently uses the same telephone or headset.

Embodiments described above illustrate but do not limit the invention.It should also be understood that numerous modifications and variationsare possible in accordance with the principles of the present invention.Although headsets are described above, the present invention may be usedin a variety of head-worn devices, such as a head-mounted computerdisplay. Accordingly, the scope of the invention is defined only by thefollowing claims.

What is claimed is:
 1. A headset system, comprising: a headset body; amicrophone coupled to the headset body; an audio transducer coupled tothe headset body; a motion detector coupled to the headset body andbeing operative to provide an output in response to movement of theheadset body; a non-motion sensor coupled to the headset body andoperative to indicate a condition that indicates a don/doff state; and aprocessor that receives the motion detector output from the motiondetector and the condition from the non-motion sensor and that indicatesa don/doff state when both the motion sensor and the non-motion sensorindicate the same state.
 2. The headset system of claim 1 wherein theprocessor is located in the headset body.
 3. The headset system of claim2 further comprising a wireless transceiver for reporting the don/doffstate over a wireless link.
 4. The headset system of claim 3 wherein thedon/doff output is reported to a server.
 5. The headset of claim 1wherein the processor resets a headset parameter when it detects achange in don/doff state from don to doff.
 6. The headset of claim 5wherein the headset parameter that is reset is headset volume.
 7. Amethod, executed by a processor in a headset system comprising a headsetbody; a microphone coupled to the headset body, an audio transducercoupled to the headset body; and a motion detector coupled to theheadset body and being operative to provide an output in response tomovement of the headset body and a non-motion sensor coupled to theheadset body and operative to indicate a condition that indicates adon/doff state, the method comprising: monitoring the motion detectoroutput to determine whether it indicates a don state or a doff state;monitoring the non-motion sensor output to determine whether itindicates a don state or a doff state; and providing a don/doff stateoutput when both the motion sensor and the non-motion sensor indicatethe same state.
 8. The method of claim 7 further comprising reportingthe don/doff state output over a wireless link.
 9. The method of claim 8wherein the don/doff state output is reported to a server.
 10. Themethod of claim 7 further comprising: resetting a headset parameter whena change in don/doff state from don to doff is determined.
 11. Themethod of claim 10 wherein the headset parameter that is reset isheadset volume.